Answer:
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The chef used 800g out of a 5kg bag of flour, so the amount of flour left is 5,000g - 800g = 4,200g. To find the percentage of flour left, divide the amount of flour left by the total amount of flour and multiply by 100: (4,200g / 5,000g) * 100 = 84%. So 84% of the flour is left.